Your iPhone battery will last longer with iOS 9.
At WWDC 2015, Apple senior vice president of software engineering Craig Federighi announced iOS 9 will extend battery life on iPhones by one hour. Another "Low Power Mode" will extend battery life up to three more hours on top of that.
Low Power Mode is indicated by a yellow battery life icon. Android smartphones like the Samsung Galaxy phones have had special power-savings modes for a while.
Federighi didn't specify what the extra three hours actually referred to. Three extra hours of talk time? On Wi-Fi? On a 4G LTE connection? We'll update as we find out.
With iOS 8, the iPhone 6's battery lasts up to 14 hours on 3G for talk time, up to 10 hours of 3G and 4G LTE Internet use, up to 11 hours on Wi-Fi. It gets up to 11 hours for HD video playback and up to 50 hours for music playback.
Update 6/9/15 10:27 a.m. ET: Low Power Mode limits network activity by switching the Mail app to fetching manually, disabling background app refresh and downloads, reducing motion and brightness, and reducing network speed.
[nggallery id= 23000]